An organic light-emitting device, which is generally called as EL (Electroluminescence device), is one of the representative flat-panel display devices along with Liquid Crystal Display(LCD), Plasma Display Panel(PDP), and Field Emission Display(FED). The organic light-emitting device does not require a back-light for light-emitting, and can be manufactured into a thin film and flexible device, and mass-produced by the well-known film fabrication techniques. In addition, the EL is a self-light emitting device. Therefore, the EL has not only a fast response speed but also an excellent brightness and wide viewing angle. Also, the EL can be operated with a low driving voltage, and display full colors in a visible region. In the organic light-emitting device, an organic light-emitting layer having a light-emitting property is interposed between a transparent electrode made of ITO et al. having a high work function and a metal electrode made of Mg et al. having a low work function. When a voltage is applied to the electrodes, holes and electrons are generated at the electrodes, and recombined at the organic light-emitting layer to induce a light-emission. To produce a full-color organic light-emitting device, it is necessary to prepare organic light-emitting compounds for emitting red(R), green(G) or blue(B) light.
A Spiro compound is one of the well-known organic light-emitting compounds. For example, U.S. Pat. No. 5,840,217 discloses spiro-single compounds such as spiro-triphenylamine, spiro-N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (spiro-TPD), spiro-benzoxazole, spiro-sexiphenyl, and so on. U.S. Pat. No. 5,741,921 discloses spiro-compounds in which the spiro atom of the spiro-compound is Sn, Si, or so on instead of carbon. U.S. Pat. No. 6,211,369 discloses spiro-compounds in which at least one aromatic groups of the spiro-compound is a heteroaryl group. U.S. Pat. Nos. 5,621,131 and 5,763,636 disclose spiro-polymers in which the repeating unit of the polymer is a spiro-compound. Also, Japanese Laid-open patent No. 2001-131434 discloses organic light-emitting compounds in which two aromatic groups are linked with an anthracene group. These conventional spiro-compounds have a good heat-resistance, but the blue light emitting efficiency thereof is not satisfactory. Furthermore, it is not easy to form a layer with the spiro-compounds by a conventional vacuum deposition process. Thus, the organic light-emitting layer made of the spiro-compounds is conventionally manufactured by a spin-coating process, which decreases the productivity of the organic light-emitting device.